Otitoma philippinensis, Morassi & Nappo & Bonfitto, 2017

Morassi, Mauro, Nappo, Andrea & Bonfitto, Antonio, 2017, New species of the genus Otitoma Jousseaume, 1898 (Pseudomelatomidae, Conoidea) from the Western Pacific Ocean, European Journal of Taxonomy 304, pp. 1-30 : 21

Otitoma philippinensis sp. nov.

urn:lsid:zoobank.org:act:2E5D9D74-C5CB-4C19-9D6A-D0AF85DBC669

Fig. 5 P–U

Etymology

The specific name is derived from the country of the origin of the type.

Type material

Holotype

PHILIPPINES: Nocnocan Island , 180–250 m, trawled by fishermen ( MZB 60215 ).

Paratype

PHILIPPINES: Mactan Island, 200 m, trawled by fishermen ( MM collection).

Description

Shell fusiform (b/l 0.33–0.34; a/l 0.46–0.47). Teleoconch of 6 convex whorls with periphery below mid-whorl height on earliest four whorls, at mid-whorl on later two whorls. Whorls separated by a distinct suture bordered by a weakly prominent spiral cord. Sutural ramp rather wide and shallowly concave. Axial sculpture consisting of opisthocline ribs, subequal to broader than intercoastal spaces, extending on spire whorls from suture to abapical side of sub-sutural ramp, prominent on earlier whorls but becoming much weaker on last whorl. 15 axial ribs on penultimate whorl, becoming obsolete on last whorl. Spiral sculpture consisting of widely-spaced, narrow, moderately prominent spiral cords, plicate where they cross axial ribs. First three teleoconch whorls with two cords between sub-sutural ramp and abapical suture, increasing to three cords on following three whorls. Last whorl with 13-15 spiral cords on base and rostrum. Intercostal spaces sculptured by numerous very fine spiral threads (up to about 13) ( Fig. 5 R–S). Aperture rather narrow, lanceolate, constricted at entrance to siphonal canal. Siphonal canal long for genus, not notched terminally. Inner lip with moderately thin callus, parietal region with a pad formed by termination of outer lip. Outer lip preceded by a wide, prominent, rounded varix; edge of lip sharp. Anal sinus moderately deep, asymmetrically U-shaped, with constricted opening. Stromboid notch moderately deep. Protoconch narrowly conical, of three smooth whorls ( Fig. 5 T–U), diameter 0.80 mm. Color yellowish-white tinged, with light brown on sub-sutural ramp, along peripheral cord and at level of abapical suture.

Dimensions

Holotype: 15.4 × 5.25 mm, aperture height 7.1 mm. Paratype: 15.3 × 5.1 mm, aperture height 7.2 mm.

Remarks

This species is characterized by its large size, wide sutural ramp and well developed sculpture on the abapical side of each whorl. It is very similar to an undescribed species occurring in the Philippines and represented in the available material by a single large (17.9 × 6.3 mm), but damaged specimen from the Solomon Islands [SALOMON 1, Stn DW1768], which will be described by other authors elsewhere. The main difference is that in O. philippinensis sp. nov. there are two peripheral spiral cords on the earliest three whorls, increasing to 3 on later whorls; one very weak spiral cord is also present at the level of the abapical suture of the later whorls. In the undescribed species there are two main peripheral spiral cords bordered by a third, weaker cord on the abapical part of the sutural ramp and one (earlier whorls) increasing to 2 cords (later two whorls) at the level of the abapical suture. A further distinguishing feature is represented by its color pattern. Otitoma philippinensis sp. nov. is yellowish-white, tinged light brown on the sutural ramp, along the peripheral cord and at the level of the abapical suture, while the undescribed species is more vividly patterned with two well defined and intense brown bands.

Figures

Fig. 5. [next page] A–H. Otitoma rubiginostoma sp. nov. A–B. Holotype (MNHN IM-2000- 32604), MUSORSTOM 4, Stn DW151, New Caledonia, 19°07′ S, 163°22′ E, 200 m, 4.7 × 1.8 mm. C–H. Paratype 2 (MZB 60214), MUSORSTOM 4, Stn DW149, New Caledonia, 19°08′ S, 163°23′ E, 155 m. D. Teleoconch. E. Secondary spiral sculpture of the teleoconch. F–G Protoconch. H. Microsculpture of the protococonch. — I–O. Otitoma elegans sp. nov. I–J. Holotype (MNHN IM-2000-32606), BORDAU 1, Stn DW1465, Fiji Island, 18°09′ S, 178°39′ W, 290–300 m, 12.6 × 4.8 mm. K. Teleoconch (not coated). L. Secondary spiral sculpture of the teleoconch (not coated). M, O. Protoconch (not coated). N. Microsculpture of the protococonch. — P–U. Otitoma philippinensis sp. nov. P–Q. Holotype (MZB 60215), Philippines, Nocnocan Island, 180–250 m, trawled by fishermen, 15.4 × 5.25 mm. R. Teleoconch (not coated). S. Secondary spiral sculpture of the teleoconch (not coated). T–U. Protoconch (not coated). Scale bars: C, K = 1 mm; D, F–G, L–N, S–U = 100 µm; E, H, O = 50 µm; R = 500 µm.